Concerns regarding global climate change coupled with increased energy consumption have galvanized the search for sustainable alternative energy conversion and storage systems. Much attention has been directed to the use of lithium batteries, such as lithium-ion batteries. While lithium-ion batteries have been shown to have a high energy density and efficiency, the current energy storage capability of lithium-ion batteries is not sufficient for certain applications, such as batteries for electrical vehicles. To address this deficiency, lithium-air batteries have emerged as a viable alternative to lithium-ion batteries for certain applications, due to the relatively high energy storage capacity compared to other rechargeable batteries.
Lithium-air batteries use the oxidation of lithium metal at the anode and the reduction of oxygen from air at the cathode to induce current flow. Theoretically, the specific energy possible with lithium-air batteries is comparable to the specific energy of gasoline. Thus, lithium-air batteries have the potential to provide electric vehicles with substantially the same range as gasoline vehicles. However, the high reactivity of lithium metal has hampered its use in commercial batteries. Lithium metal anodes, such as those used in lithium-air batteries, are known to decompose many battery electrolytes and form dendritic growths that short circuit the battery, thereby limiting battery lifetime. Accordingly, improved compositions that extend battery lifetime without compromising performance are needed.